undercarriage service?

In 6 years dealing with Rpods I have never heard of undercarriage service.

We took our pod in to have the seals checked and were asked if we wanted the undercarriage service done, as well. They said they advise people who buy trailers from them to have it done after the first year, then every 8000-10,000 miles.  We have about 2000 miles on ours after about 3 years and are wondering if anyone has any advice about this servicing. We are inclined to wait for the 8000 miles, but don't want to miss doing something that is needed.